Method for producing a monolithic front air deflector

ABSTRACT

An air deflector for attachment to a lower surface of a vehicle includes a first portion and a second portion attached to and extending downwardly from the first portion. The first portion is adapted to be attached to a lower surface of the vehicle and is formed of a first material having a first durometer value. The second portion is formed of a second material different from the first material. The second portion has a second durometer value less than the first durometer value.

RELATED APPLICATION

This application is a division of U.S. Ser. No. 10/178,286 filed on Jun.24, 2002, now U.S. Pat. No. 6,874,842.

BACKGROUND OF THE INVENTION

The present invention relates generally to air deflectors for automotivevehicles and, in particular, to an air deflector for attachment to alower surface of a vehicle and a method for producing the air deflector.

Air dams, or air deflectors, for attachment to surfaces of an automobilebody are well known. Air deflectors are typically a rigid panelinstalled below the front bumper on most modern vehicles to directairflow thereby reducing drag and lift and increasing heat exchangercooling. The air deflector diverts air flowing under the vehicle awayfrom suspension and frame components thus reducing the drag of thevehicle. In addition, the pressure behind the air deflector isdecreased, which aids the cooling flow across the radiator. Thedeflector also functions to reduce lift at the front of the vehicle.

A typical prior art air deflector assembly design for vehicles is asingle piece design. Some vehicle designs, however, require amulti-piece air deflector to accommodate vehicle air flow dynamics. Themulti-piece air deflector includes a three piece design consisting ofupper and lower hard plastic material panels joined together with aspring-loaded hinge device. The spring-loaded hinge is used fordeflection purposes of the lower portion when approaching and/or goingover objects such as curbs, parking bumpers or transitions between roadsand driveways. The assembly is fastened to a skid bar on the undersideof the vehicle with nuts and bolts.

This type of prior art air deflector assembly, however, has proved to beextremely costly to manufacture. The prior art assembly alsodisadvantageously creates a disturbing noise when in contact with curbsor driveways, and there is an excessive deflection of the lower portionat high speeds resulting in loss of cooling and aerodynamiccharacteristics. In addition, the prior art assembly has a high warrantycost because of both the high cost and the high frequency of replacingbroken air deflectors.

It is desirable, therefore, to provide an air deflector assembly for anautomotive vehicle that is cost-effective to produce, does not createdisturbing noises when in contact with curbs or driveways and does notdeflect excessively at high speeds.

SUMMARY OF THE INVENTION

The present invention concerns an air deflector for attachment to alower surface of a vehicle. The air deflector includes a first portionformed of a first plastic material having a first durometer value and isadapted to be attached to a lower surface of a vehicle. The airdeflector also includes a second portion attached to and extendingdownwardly from the first portion. The second portion is formed of asecond material that is different from said first material and having asecond durometer value that is less than the first durometer value.Preferably, the first material is a hard polypropylene plastic materialand the second material is a softer, rubberized plastic material, suchas 101-80 durometer thermoplastic elastomer (TPE). Preferably, the airdeflector according to the present invention is used for a front centerair deflector, where the first portion is adapted to be mounted to askid bar on a lower surface of the vehicle.

The present invention relates to a unique design utilizing twodistinctive plastic compounds in an integral air deflector to enhanceair deflector function and performance. The present invention solves theshortcomings of the prior art air deflector assembly by providing aone-piece injection molded dual durometer front center air deflectorassembly. The present invention provides many advantages over the priorart including, but not limited to, a substantially lower cost design,and the second portion of the air deflector is a softer durometermaterial and is barely audible when coming in contact with curbs ordriveways. The second portion of the air deflector also hassubstantially less deflection than the lower portion of the prior artdeflector assembly, resulting in better airflow and aerodynamiccharacteristics. Furthermore, because of the characteristics of thesecond material, it is anticipated that the present invention willreduce warranty claims substantially.

The novelty of the present invention is the utilization of twodistinctive plastic compounds in an integral one-piece injection moldedair deflector to provide rigid mounting to the vehicle, reduced inclineand curb scrub noise, and consistent vehicle aerodynamiccharacteristics.

The air deflector according to the present invention is preferablyproduced by an injection molding method, as follows. The first portionof the air deflector having a first durometer value is formed first,preferably by an injection molding. The first portion is also preferablyseparated from the second portion molding area in the first shot moldingprocess by a separator that is known in the art as a blade. The blade isthen removed and the second portion of the air deflector made of asofter durometer is shot into the mold, thereby fusing the first portionand the second portion together with a tongue and groove joint design.

DESCRIPTION OF THE DRAWINGS

The above, as well as other advantages of the present invention, willbecome readily apparent to those skilled in the art from the followingdetailed description of a preferred embodiment when considered in thelight of the accompanying drawings in which:

FIG. 1 is a perspective view of an air deflector in accordance with thepresent invention;

FIG. 2 is cross-sectional view taken along line 2—2 of the air deflectorshown in FIG. 1; and

FIG. 3 is a perspective view of the air deflector of FIG. 1 shownadjacent a lower surface of a vehicle.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to FIGS. 1 and 2, an air deflector according to thepresent invention is indicated generally at 10. The air deflector 10includes a first portion 12 and a second portion 14 attached thereto andextending downwardly therefrom to form a generally vertical plane. Thefirst portion 12 is horizontally elongated and is adapted to be attachedto a lower surface of a vehicle, outlined in more detail below. Thefirst portion 12 is preferably constructed of a first material having afirst durometer value. The first material is preferably a plasticmolding material such as polypropylene that has a high durometer value.The high durometer value indicates that the first material has a highhardness property. Preferably the first material is hard and durableenough to be mounted on the lower surface of the vehicle. The secondportion 14 is preferably constructed of a second material having asecond durometer value. The second material is different than the firstmaterial and the second durometer value is less than the first durometervalue. The second material is preferably a plastic molding material suchas a thermoplastic elastomer (TPE) that has a low durometer value. Thelow durometer value indicates that the second material has a lowhardness property. Preferably the second material is soft and pliableenough to act as a sacrificial material when the second portion 14strikes the ground (not shown) during operation of the vehicle. Thefirst portion 12 and the second portion 14 are joined at a seam 16,preferably by a tongue and groove connection, whereby an upper edge 17of the second portion 14 includes a groove 15 that engages with a tongue13 extending downwardly from a lower edge 19 of the first portion 12.Alternatively, other means are used to join the first portion 12 and thesecond portion 14 along the seam 16.

The first portion 12 includes an outer surface 18 and an inner surface20. The inner surface 20 includes a plurality of projections 22extending outwardly therefrom for facilitating attachment to a skidplate, such as a skid plate 34 in FIG. 3, on a lower surface of avehicle (not shown). An upper portion 24 of the first portion 12 iscurved inwardly to facilitate directing the airflow by the air deflector10. The outer surface 18 of the first portion 12 is smooth in order tofacilitate directing the airflow around the vehicle. A tab 25 on eachopposite end of an upper edge of the upper portion 12 for facilitatingattachment with the skid plate extends outwardly in an oppositedirection from the projections 22.

The second portion 14 includes an outer surface 26 and an inner surface28. The outer surface 26 is smooth in order to facilitate directing theairflow around the vehicle. A lower portion 30 of the second portion 14is curved inwardly to facilitate directing the airflow by the airdeflector 10.

Referring now to FIG. 3, the air deflector 10 is shown adjacent avehicle frame, indicated generally at 32. The vehicle frame 32 includesthe skid plate 34 attached to a bottom surface thereof. The skid plate34 and the frame 32 are shown adjacent a radiator baffle assembly andsupport, indicated generally at 35. The radiator baffle assembly andsupport 35 is attached to an upper surface of the skid plate 34. Theskid plate 34 is operable to attach to the air deflector 10 by aplurality of nuts 36 and bolts 38 extending through a plurality ofapertures 40 on the skid plate 34 and a plurality of apertures 42 on theair deflector 10. Preferably the projections 22 on the inner surface 20cooperate with projections (not shown) on the frame 32 or the skid plate34 to facilitate attachment of the air deflector 10 to the skid plate34.

The air deflector 10 is produced by the steps of providing the firstplastic molding material and forming the first portion 12 from the firstmolding material. The next step is providing the second plastic materialand forming the second portion 14 from the second molding material. Thenext step is joining the first portion 12 to the second portion 14 toform the air deflector 10.

Preferably, the steps outlined above for producing the air deflector 10are a part of an injection molding process whereby the first material isinjected into a first molding area 46 of a mold 44 and the first portion12 is preferably separated in the first shot molding process from asecond molding area 48 of the mold 44, best seen in FIG. 2, by aseparator (not shown) that is known in the art as a blade. The blade isthen removed and the second material is injected into the second area 48of the same mold 44 thereby fusing the first portion 12 and the secondportion 14 together to form the air deflector 10.

In accordance with the provisions of the patent statutes, the presentinvention has been described in what is considered to represent itspreferred embodiment. However, it should be noted that the invention canbe practiced otherwise than as specifically illustrated and describedwithout departing from its spirit or scope.

1. A method for producing a monolithic front air deflector, the airdeflector adapted to be attached to a lower surface of an automotivevehicle and to deflect air as the vehicle moves forward, comprising thesteps of: a) providing a first plastic molding material; b) forming afirst portion of the air deflector from said first plastic moldingmaterial, said first portion having a first durometer value and adaptedto be attached to said lower front surface of said vehicle; c) providinga second plastic molding material different than said first plasticmolding material; d) forming a second portion of the air deflector fromsaid second plastic molding material, said second portion having asecond durometer value less than said first durometer value; and e)fusing said first portion to said second portion to form the airdeflector wherein said second portion is fused to said first portion toprevent detachment therefrom and movement therebetween and extenddownwardly from said first portion.
 2. The method according to claim 1wherein said first plastic molding material is polypropylene.
 3. Themethod according to claim 1 wherein said second molding material is alow durometer thermoplastic elastomer.
 4. The method according to claim1 wherein said steps are performed as part of an injection moldingprocess.
 5. The method according to claim 1 including steps of providinga mold having a first molding area and a second molding area; separatingsaid first molding area from said second molding area; performing saidstep b. in said first molding area; exposing said first molding area tosaid second molding area; performing said step d. in said second moldingarea; performing said step e.; at an interface of said first moldingarea with said second molding area; and removing the air deflector fromthe mold.
 6. The method according to claim 5 including forming a tongueon said first portion during said step b. and forming a groove in saidsecond portion during said step d., said tongue and said groovecooperating to join said first portion to said second portion.